Toxicity in overdose is rare and not expected. The majority of toxic effects are related to drug interactions because these agents competitively inhibit CYP3A4. Overdose and inadvertent exposures are uncommon and serious toxicity from acute ingestion has not been reported. Overdose effects would be expected to be similar to adverse effects reported after therapeutic use. Adverse effects include nausea. vomiting, diarrhea, abdominal pain, hypokalemia, and visual changes (abnormal vision, color vision changes, photophobia). There are reports of dizziness, hepatotoxicity, congestive heart failure, thrombocytopenia, neutropenia, seizures, and delirium. Azole antifungals have been implicated in case reports to cause toxic epidermal necrolysis and less serious rashes.
Treatment: Management of mild to moderate toxicity: Treatment is symptomatic and supportive. Correct any significant fluid and/or electrolyte abnormalities in patients with severe diarrhea and/or vomiting. Antiemetic medications and IV fluids can be used for gastrointestinal distress.
Management of severe toxicity: Treatment is symptomatic and supportive. Severe toxicity is not expected after fluconazole (or related agents) overdose. Most overdoses do not lead to toxicity. Prehospital gastrointestinal decontamination is generally not required and activated charcoal is typically not recommended. There is no antidote.